dissenting.
The Court today holds that the exclusionary rule does not apply in civil deportation proceedings. Because I believe that the conclusion of the majority is based upon an incorrect assessment of the costs and benefits of applying the rule in such proceedings, I respectfully dissent.1
The paradigmatic case in which the exclusionary rule is applied is when the prosecutor seeks to use evidence illegally obtained by law enforcement officials in his case in chief in a criminal trial. In other classes of cases, the rule is applicable only when the likelihood of deterring the unwanted conduct outweighs the societal costs imposed by exclusion of relevant evidence. United States v. Janis, 428 U. S. 433, 454 (1976). Thus, the Court has, in a number of situations, refused to extend the exclusionary rule to proceedings other than the criminal trial itself. For example, in Stone v. Powell, 428 U. S. 465 (1976), the Court held that the deterrent effect of the rule would not be reduced by refusing to allow a state prisoner to litigate a Fourth Amendment claim in federal habeas corpus proceedings if he was afforded a full and fair opportunity to litigate it in state court. Similarly, in United *1053States v. Calandra, 414 U. S. 338, 351 (1974), we concluded that “[a]ny incremental deterrent effect which might be achieved by extending the rule to grand jury proceedings is uncertain at best.” And in United States v. Janis, supra, we declined to extend the exclusionary rule to bar the introduction in a federal civil proceeding of evidence unconstitutionally seized by a state law enforcement officer. In all of these cases it was unquestioned that the illegally seized evidence would not be admissible in the case in chief of the proceeding for which the evidence was gathered; only its collateral use was permitted.
Civil deportation proceedings are in no sense “collateral.” The majority correctly acknowledges that the “primary objective” of the INS agent is “to use evidence in the civil deportation proceeding” and that “the agency officials who effect the unlawful arrest are the same officials who subsequently bring the deportation action.” Ante, at 1043. The Immigration and Naturalization Service likewise concedes that INS agents are “in the business of conducting searches for and seizures of illegal aliens for the purpose of bringing about their deportation.” Brief for Petitioner 37. Thus, unlike the situation in Janis, the conduct challenged here falls within “the offending officer’s zone of primary interest.” 428 U. S., at 458. The majority nonetheless concludes that application of the rule in such proceedings is unlikely to provide significant deterrence. Because INS agents are law enforcement officials whose mission is closely analogous to that of police officers and because civil deportation proceedings are to INS agents what criminal trials are to police officers, I cannot agree with that assessment.
The exclusionary rule rests on the Court’s belief that exclusion has a sufficient deterrent effect to justify its imposition, and the Court has not abandoned the rule. As long as that is the case, there is no principled basis for distinguishing between the deterrent effect of the rule in criminal cases and in civil deportation proceedings. The majority attempts to justify the distinction by asserting that deportation will still *1054be possible when evidence not derived from the illegal search or seizure is independently sufficient. Ante, at 1043-1044. However, that is no less true in criminal cases. The suppression of some evidence does not bar prosecution for the crime, and in many cases even though some evidence is suppressed a conviction will nonetheless be obtained.
The majority also suggests that the fact that most aliens elect voluntary departure dilutes the deterrent effect of the exclusionary rule, because the infrequency of challenges to admission of evidence will mean that “the consequences from the point of view of the officer’s overall arrest and deportation record will be trivial.” Ante, at 1044. It is true that a majority of apprehended aliens elect voluntary departure, while a lesser number go through civil deportation proceedings and a still smaller number are criminally prosecuted. However, that fact no more diminishes the importance of the exclusionary sanction than the fact that many criminal defendants plead guilty dilutes the rule’s deterrent effect in criminal cases. The possibility of exclusion of evidence quite obviously plays a part in the decision whether to contest either civil deportation or criminal prosecution. Moreover, in concentrating on the incentives under which the individual agent operates to the exclusion of the incentives under which the agency as a whole operates neglects the “systemic” deterrent effect that may lead the agency to adopt policies and procedures that conform to Fourth Amendment standards. See, e. g., Dunaway v. New York, 442 U. S. 200, 221 (1979) (Stevens, J., concurring).
The majority believes “perhaps most important” the fact that the INS has a “comprehensive scheme” in place for deterring Fourth Amendment violations by punishing agents who commit such violations, but it points to not a single instance in which that scheme has been invoked.2 Ante, at *10551044-1045. Also, immigration officers are instructed and examined in Fourth Amendment law, and it is suggested that this education is another reason why the exclusionary rule is unnecessary. Ibid. A contrary lesson could be discerned from the existence of these programs, however, when it is recalled that they were instituted during “a legal regime in which the cases and commentators uniformly sanctioned the invocation of the rule in deportation proceedings.” 705 F. 2d 1059, 1071 (CA9 1983). Thus, rather than supporting a conclusion that the exclusionary rule is unnecessary, the existence of these programs instead suggests that the exclusionary rule has created incentives for the agency to ensure that its officers follow the dictates of the Constitution. Since the deterrent function of the rule is furthered if it alters either “the behavior of individual law enforcement officers or the policies of their departments,” United States v. Leon, ante, at 918, it seems likely that it was the rule’s deterrent effect that led to the programs to which the Court now points for its assertion that the rule would have no deterrent effect.
The suggestion that alternative remedies, such as civil suits, provide adequate protection is unrealistic. Contrary to the situation in criminal cases, once the Government has improperly obtained evidence against an illegal alien, he is removed from the country and is therefore in no position to file civil actions in federal courts. Moreover, those who are legally in the country but are nonetheless subjected to illegal searches and seizures are likely to be poor and uneducated, and many will not speak English. It is doubtful that the threat of civil suits by these persons will strike fear into the hearts of those who enforce the Nation’s immigration laws.
It is also my belief that the majority exaggerates the costs associated with applying the exclusionary rule in this context. Evidence obtained through violation of the Fourth Amendment is not automatically suppressed, and any inquiry *1056into the burdens associated with application of the exclusionary rule must take that fact into account. In United States v. Leon, ante, p. 897, we have held that the exclusionary rule is not applicable when officers are acting in objective good faith. Thus, if the agents neither knew nor should have known that they were acting contrary to the dictates of the Fourth Amendment, evidence will not be suppressed even if it is held that their conduct was illegal.
As is noted ante, at 1051, n. 5, the BIA has already held that evidence will be suppressed if it results from egregious violations of constitutional standards. Thus, the mechanism for dealing with suppression motions exists and is utilized, significantly decreasing the force of the majority’s predictions of dire consequences flowing from “even occasional invocation of the exclusionary rule.” Ante, at 1048. Although the standard currently utilized by the BIA may not be precisely coextensive with the good-faith exception, any incremental increase in the amount of evidence that is suppressed through application of Leon is unlikely to be significant. Likewise, any difference that may exist between the two standards is unlikely to increase significantly the number of suppression motions filed.
Contrary to the view of the majority, it is not the case that Sandoval-Sanchez’ “unregistered presence in this country, without more, constitutes a crime.” Ante, at 1047. Section 275 of the Immigration and Nationality Act makes it a crime to enter the United States illegally. 8 U. S. C. § 1325.3 The first offense constitutes a misdemeanor, and subsequent offenses constitute felonies. Ibid. Those few cases that have construed this statute have held that a violation takes *1057place at the time of entry and that the statute does not describe a continuing offense. Gonzales v. City of Peoria, 722 F. 2d 468, 473-474 (CA9 1983); United States v. Rincon-Jimenez, 595 F. 2d 1192, 1194 (CA9 1979). Although this Court has not construed the statute, it has suggested in dictum that this interpretation is correct, United States v. Cores, 356 U. S. 405, 408, n. 6 (1958), and it is relatively clear that such an interpretation is most consistent with the statutory language. Therefore, it is simply not the case that suppressing evidence in deportation proceedings will “allo[w] the criminal to continue in the commission of an ongoing crime.” Ante, at 1047. It is true that some courts have construed § 276 of the Act, 8 U. S. C. § 1326, which applies to aliens previously deported who enter or are found in the United States, to describe a continuing offense.4 United States v. Bruno, 328 F. Supp. 815 (WD Mo. 1971); United States v. Alvarado-Soto, 120 F. Supp. 848 (SD Cal. 1954); United States v. Rincon-Jimenez, supra (dictum). But see United States v. DiSantillo, 615 F. 2d 128 (CA3 1980). In such cases, however, the Government will have a record of the prior deportation and will have little need for any evidence that might be suppressed through application of the exclusionary rule. See United States v. Pineda-Chinchilla, 712 F. 2d 942 (CA5 1983) (illegality of arrest does not bar introduction of INS records to demonstrate prior deportation), cert. denied, 464 U. S. 964 (1983).
Although the majority relies on the registration provisions of 8 U. S. C. §§ 1302 and 1306 for its “continuing crime” argument, those provisions provide little support for the general *1058rule laid down that the exclusionary rule does not apply in civil deportation proceedings. First, §1302 requires that aliens register within 30 days of entry into the country. Thus, for the first 30 days failure to register is not a crime. Second, § 1306 provides that only willful failure to register is a misdemeanor. Therefore, “unregistered presence in this country, without more,” ante, at 1047, does not constitute a crime; rather, unregistered presence plus willfulness must be shown. There is no finding that Sandoval-Sanchez willfully failed to register, which is a necessary predicate to the conclusion that he is engaged in a continuing crime. Third, only aliens 14 years of age or older are required to register; those under 14 years of age are to be registered by their parents or guardian. By the majority’s reasoning, therefore, perhaps the exclusionary rule should apply in proceedings to deport children under 14, since their failure to register does not constitute a crime.
Application of the rule, we are told, will also seriously interfere with the “streamlined” nature of deportation hearings because “[n] either the hearing officers nor the attorneys participating in those hearings are likely to be well versed in the intricacies of Fourth Amendment law.” Ante, at 1048. Yet the majority deprecates the deterrent benefit of the exclusionary rule in part on the ground that immigration officers receive a thorough education in Fourth Amendment law. Ante, at 1044-1045. The implication that hearing officers should defer to law enforcement officers’ superior understanding of constitutional principles is startling indeed.
Prior to the decision of the Board of Immigration Appeals in Matter of Sandoval, 17 I. & N. Dec. 70 (1979), neither the Board nor any court had held that the exclusionary rule did not apply in civil deportation proceedings. 705 F. 2d, at 1071. The Board in Sandoval noted that there were “fewer than fifty” BIA proceedings since 1952 in which motions had been made to suppress evidence on Fourth Amendment *1059grounds. This is so despite the fact that “immigration law practitioners have been informed by the major treatise in their field that the exclusionary rule was available to clients facing deportation. See 1A C. Gordon and H. Rosenfield, Immigration Law and Procedure §5.2c at 5-31 (rev. ed. 1980).” 705 F. 2d, at 1071. The suggestion that “[t]he prospect of even occasional invocation of the exclusionary rule might significantly change and complicate the character of these proceedings,” ante, at 1048, is thus difficult to credit. The simple fact is that prior to 1979 the exclusionary rule was available in civil deportation proceedings, and there is no indication that it significantly interfered with the ability of the INS to function.
Finally, the majority suggests that application of the exclusionary rule might well result in the suppression of large amounts of information legally obtained because of the “crowded and confused circumstances” surrounding mass arrests. Ante, at 1049. The result would be that INS agents would have to keep a “precise account of exactly what happened in each particular arrest,” which would be impractical considering the “massed numbers of ascertainably illegal aliens.” Ante, at 1049-1050. Rather than constituting a rejection of the application of the exclusionary rule in civil deportation proceedings, however, this argument amounts to a rejection of the application of the Fourth Amendment to the activities of INS agents. If the pandemonium attending immigration arrests is so great that violations of the Fourth Amendment cannot be ascertained for the purpose of applying the exclusionary rule, there is no reason to think that such violations can be ascertained for purposes of civil suits or internal disciplinary proceedings, both of which are proceedings that the majority suggests provide adequate deterrence against Fourth Amendment violations. The Court may be willing to throw up its hands in dismay because it is administratively inconvenient to determine whether *1060constitutional rights have been violated, but we neglect our duty when we subordinate constitutional rights to expediency in such a manner. Particularly is this so when, as here, there is but a weak showing that administrative efficiency will be seriously compromised.
In sum, I believe that the costs and benefits of applying the exclusionary rule in civil deportation proceedings do not differ in any significant way from the costs and benefits of applying the rule in ordinary criminal proceedings. Unless the exclusionary rule is to be wholly done away with and the Court's belief that it has deterrent effects abandoned, it should be applied in deportation proceedings when evidence has been obtained by deliberate violations of the Fourth Amendment or by conduct a reasonably competent officer would know is contrary to the Constitution. Accordingly, I dissent.
I also question the Court’s finding that Lopez-Mendoza failed to object to admission of the evidence. Ante, at 1040, and n. 1. The Court of Appeals held that he had made a proper objection, 705 F. 2d 1059, 1060, n. 1 (CA9 1983), and the INS did not seek review of that conclusion, Brief for Petitioner 8, n. 8. Moreover, the fact that changes in an opinion are made between the time of the slip opinion and the bound volume has never before been considered evidence that the holding of a case is “unsettled.” See ante, at 1040, n. 1.
The INS suggests that its disciplinary rules are “not mere paper procedures” and that over a period of four years 20 officers were suspended or terminated for misconduct toward aliens. Brief for Petitioner 45, n. 28. The INS does not assert, however, that any of these officers were disci*1055plined for Fourth Amendment violations, and it appears that the 11 officers who were terminated were terminated for rape or assault. See Brief for Respondents 60, n. 42.
Section 275 provides in part:
“Any alien who (1) enters the United States at any time or place other than as designated by immigration officers, or (2) eludes examination or inspection by immigration officers, or (3) obtains entry to the United States by a willfully false or misleading representation . . . shall be guilty of a [crime]. . . .” 8 U. S. C. § 1325.
Section 276 provides in part:
“Any alien who—
“(1) has been arrested and deported or excluded and deported, and thereafter
“(2) enters, attempts to enter, or is at any time found in, the United States . . .
shall be guilty of a felony.” 8 U. S. C. § 1826.